1. Field of the Invention
This invention relates in general to an improved process of making encrusted bakery products.
2. Description of the Prior Art
Up to the present, the process of making encrusted bakery products or encrusted rolls which have a bun-like shape with yeast raised bread dough as crust, and with several kinds of pasty filling, such as sweet bean paste, jam, cream or custard cream, chocholate filling, minced meat paste, or cheese base paste, is almost always carried out by hand, especially when encrusting at the final stage of the process. More specifically, in this process, an individual round bread dough of certain weight (hereinafter called "crust dough") properly treated by dividing, rounding and intermediate proofing, which will build up its outer parts surrounding the pasty filling in the center of the roll, is flattened by hand or rolled out by one or two sets of rolling pins (hereinafter called "moulder"). On a round piece of flattened crust dough, a pasty ball of the filling is deposited by hand or depositing machine (hereinafter called "depositor"). The crust dough sheet with the filling on it, is then placed on the palm of the left or right hand, and the margin of the crust dough sheet is gathered centripetally by the fingers and pressed together by the fingers of the other hand, covering up the ball of filling inside the crust dough, and making up an encrusted roll.
Then, the made up round encrusted roll is put onto a pan upside down, with the gathered part which was pressed together by the fingers at the bottom, for the next steps of final proofing and baking.
As mentioned above, much of the process is performed by hand and thus in a mass production operation, many product make-up laborers must be employed. Furthermore, there is a problem in that products made by hand have a tendency to be unstable in quality and shape owing to the variation in skill among make-up laborers.
As an alternative to the above handwork, many attempts have been made to find an improved method, basically by some form of automation of the process, using machines of different principles.
The first approaches to development of a round roll encrusting machine were made along the lines of the conventional handwork process, using a divided and rounded dough ball, making it into a flattened piece of dough and moulding it into a bowl shape in a pot, depositing filling in the bottom part and gathering the projected margin of the flattened dough from the upper level of the edge of the pot. There are several devices for making such a bowl shaped piece of dough in a pot. In one case, a flattened piece of dough is placed over a hole with a piston at its top position flush with the upper surface of a cylinder and the piston is then drawn down, sucking down the piece of dough and forming it into a bowl shape in the pot. In another device for making a flattened piece of dough into a bowl shape, a piece of dough is placed over a pot with an open top, and a piston presses the dough down into the pot, or the nozzle of a filler depositor presses the dough down into the pot and then deposits the filling on the dough as the nozzle is lifted up. There are several devices for gathering the projected margin of the dough after it has been made into a bowl-like shape in the pot for encrusting. Some attempted to gather it by a camera iris-like closer, and others by several rods which gather the margin centripetally. In every case mentioned above, gathering the margin of the dough was not successful, because the margin cannot be fully projected outwards of the edge of the pot around its entire edge. One of the reasons for this is that the dough gained from a divided piece of dough is not always exactly round in shape; another reason is that the margin of the dough is not drawn to the center of the pot evenly around its entire circumference when being made into a bowl shaped piece by pressing or suction, even when starting with a perfectly round piece of dough, owing to the difference in friction between the margin and the upper surface of the pot (Reference: U.S. Pat. No. 3,858,497, "Apparatus for manufacturing wantans containing filler", by Masayuki Ishida).
Another attempt has been made by doubling two pieces of pre-flattened dough, between which is inserted the filling. In this case, the bottom piece of flattened dough is set on a conveyor belt and the filling is deposited thereon at is center, the top piece of dough is placed over the center of the piece of filling and also the bottom piece of dough. The margin of the top piece of dough closes the gap between the top and bottom pieces of dough by dough fermentation under certain conditions of humidity and temperature during final fermentation. Products made by this method have the problem that closure at the margin of the pieces of dough is not always perfect and leakage of filling often takes place. Additionally the bottom circumferential edge of such products tends to become rather thick and dense in texture, which is not acceptable to the consumers (Reference: U.S. Pat. No. 3,050,017, "Method of producing biscuits or similar baked products and apparatus for performing the same" by Willi Mahler; U.S. Pat. No. 4,114,525, "Filler capper machine" by Gray Gurner Welch; U.S. Pat. No. 4,094,236, "Ice cream sandwich forming apparatus" by Gordon W. Holmes and U.S. Pat. No. 3,946,656, "Manufacture of filled pastry rolls" by Harry Wong Hon Hai).
Another attempt has been made by using machines having a mechanism for extruding and encrusting. These attempts have, however, been unsuccessful. The reason for the lack of success in the case of fermented bread dough is that the gluten structure of the dough has a tendency to be destroyed when extruded from a nozzle with narrow clearance so that the resulting crumb texture of the products after baking become very weak in spite of the use of improved dough recipes and/or several changes in the method of extrusion. In particular, during the first one or two days after baking, the crumb texture rapidly becomes brittle and frail, as is often seen when the bread of roll becomes stale, and yet this period just coincides with the time period that the products are put on sale. Therefore, the crumb texture is a very critical quality of such products.
Another attempt has been made by doubling two large flattened pieces of dough, between which are placed blocks of filling which are deposited at a predetermined spacing. In this case, the bottom piece of dough which is rolled by many sets of rolls from bulk bread dough is transferred to a conveyor, balls of filling are deposited on this bottom piece of dough at a predetermined spacing, the top piece of dough which is similarly rolled from bulk bread dough is placed over the bottom piece of dough and the balls of filling, and then, by using a round cutter press, both pieces of dough are cut around the balls of filling, thus producing round encrusted products. However, this method also has not been successful. One of the reasons for this is that bread or rolls made from dough rolled from bulk dough are poor in crumb structure, have less volume and are pale in color, and are thus unacceptable to consumers. Another reason is that scrap dough remaining after cutting out cannot be mixed with new dough because it makes the dough quality poor if it is remixed, thus making inferior quality products (Reference: U.S. Pat. No. 2,386,933, "Method of and apparatus for making ravioli" by Marin Valdastri).
Another attempt has been disclosed (German Pat. No. 513833 Vorrichtung zum Herstellen von Wursten, by Otto Vetter) to mould and make encrusted food products, using one set of bowl shape moulds of the same size and hinged to each other, in one of which is placed a piece of dough with pasty filling placed thereon, and another piece of dough is placed over the filling, the mould being closed by the other bowl shape mould cover enclosing the dough pieces and filling therein, and then being clamped and baked.
This method has been well known from old times in Japan, but only for making pastry with filling encrusted inside, using a flour batter of high viscous liquid phase, and not for encrusted bread rolls made of filling and bread dough.
The reasons for this are:
(i) It is hardly possible to mould a piece of bread dough, which is not liquid but has a visco-elastic character, into an exact bowl shape shell.
(ii) Eating quality is spoiled by suppressing free fermentation expansion and also even raising of the dough with the bowl shape cover mould.
(iii) However, the margins of two pieces of flattened dough moulded in a bowl shape shell cannot be entirely sealed with each other unless the bowl shape cover mould suppresses expansion of the dough in the mould positively.
Another existing method for producing Chinese eggrolls, spring rolls, chaozu and pastries of certain kinds, consists of making flattened pieces of dough from a bulk dough block by rolling with several sets of rolls and cutting into square pieces of dough, depositing filling thereon, enclosing it by picking up and folding the four corners of the sheet, or partly folding and rolling wholly thereafter with the filling enclosed inside the dough, but this method cannot produce good quality products of desirable crumb texture and appetizing volume, when it is used for producing encrusted bread rolls using glutenous dough.
The reasons for this are:
(i) Rolling bulk dough continuously from bulk bread dough by several sets of rolls gives the dough character, especially the gluten structure of the dough, more undesirable tearing or strain than smaller scale rolling of dough pieces, and
(ii) By these processes bun-like round shaped encrusted rolls cannot be produced, which is the main object of my invention. (References: U.S. Pat. No. 3,669,007, "Method and apparatus for rolling and tucking filled stuffs" by Louis Pullel; U.S. Pat. No. 3,379,139, "Method and apparatus for quantity production of unbaked pastries" by Robert J. Lipinsky; U.S. Pat. No. 4,047,478, "Apparatus for the production of rolled food products" by Erik Trostman; and U.S. Pat. No. 4,084,493, "Apparatus for producing food stuff" by Elias Pennis Quintans, et al; U.S. Pat. No. 3,912,433, "Automatic eggroll making machine" by Kwok Chuen Ma; U.S. Pat. No. 4,014,254, "Device for wrapping sheets around food in rolled form and other food processing device" by Nobuyoshi Ohkawa; U.S. Pat. No. 2,969,025, "Pastry folder" by Leonhard Schafer, and U.S. Pat. No. 4,160,634, "Automatic dumpling making machine" by Te-Hsin Huang).